diff -r 12943ab62cc5 -r b6c0407f203e Integ/Relation.thy --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/Integ/Relation.thy Mon Feb 27 16:46:38 1995 +0100 @@ -0,0 +1,24 @@ +(* Title: Relation.thy + ID: $Id$ + Author: Riccardo Mattolini, Dip. Sistemi e Informatica + and Lawrence C Paulson, Cambridge University Computer Laboratory + Copyright 1994 Universita' di Firenze + Copyright 1993 University of Cambridge + +Functions represented as relations in Higher-Order Set Theory +*) + +Relation = Trancl + +consts + converse :: "('a*'a) set => ('a*'a) set" + "^^" :: "[('a*'a) set,'a set] => 'a set" (infixl 90) + Domain :: "('a*'a) set => 'a set" + Range :: "('a*'a) set => 'a set" + +defs + converse_def "converse(r) == {z. (? w:r. ? x y. w= & z=)}" + Domain_def "Domain(r) == {z. ! x. (z=x --> (? y. :r))}" + Range_def "Range(r) == Domain(converse(r))" + Image_def "r ^^ s == {y. y:Range(r) & (? x:s. :r)}" + +end